The present invention pertains to displays, and particularly to avionics displays. More particularly, the invention pertains to a flat panel liquid crystal display having high resolution and brightness with low power consumption.
No available electronic display meets the above-noted characteristics needed for a modern avionics display. The cathode ray tube (CRT) has a high luminous efficiency, superior contrast ratios and excellent viewing angles. However, two deficiencies of the CRT are the bulk of the electron gun and large power usage by the deflection amplifiers. There has been much effort expended over the years to develop a flat CRT. Two approaches in the development involved, first, folding the electron gun around to be in parallel with the tube face; and second, producing an electron beam for each pixel by means of an areal cathode and a grid system. Of these approaches, the first one was implemented in the SONY WATCHMAN portable television and the second one was used in a vacuum fluorescent display (VFD) of ISE. These were the only commercial successes of such approaches.
Others have demonstrated the use of a cone field emitter array (CFEA) as the areal cathode. However, both VFD and the CFEA device do not use high luminous efficiency phosphors from which one can obtain from cathodluminescence by employing a high voltage anode circuit. The CFEA device cannot use a high voltage anode because of reliability problems due to field forming of the emitter tip and emitter erosion by particles desorbed, from surfaces by electrons.
A device is needed that retains the advantages of cathodluminescence such as high brightness, high luminous efficiency and good angular viewability, but has the features of compact thinness, random addressability and low power consumption.